Advice about Crack in transom cap, 12' Gregor Aluminum

[GlormRax]

I'm not sure if this is the right subforum or if it belongs in the other general sub. Admins please adjust as desired.

I'm starting the work on repairing the transom board in my (new to me) 1977 12' Gregor. After getting the motor and transom pad off, found that there's a crack in the cap of the transom. Thoughts on repair? I don't weld, fyi. I think the one rivet was placed by the PO.

 

[Scott Danforth]

pull the cap, check the wood, replace as needed, take cap to radiator shop to have welded (spend $20) replace cap.

 

[GlormRax]

Unfortunately it's not a separate cap, I just used that term for lack of a better way to describe it. It's the top edge of the transom that wraps over the transom board. My concern is that the crack could "travel" and eventually turn the corner down the face of the transom. I'm probably not describing it very well.

Maybe I'm being overly cautious and should just leave it alone?

 

[GA_Boater]

Can you take a couple more pics showing the full width of the stern, inside and outside? It sure does look like a U shaped channel that covers the top of the transom, even the inside pic with the crack coming over the top and starting down the inside, pic #3.

 

[Scott Danforth]

it most likely cracked because your transom is flexing

your transom is flexing because the wood may be rotten.

you need to check your transom

every radiator shop welds aluminum (cheap)

 

[GlormRax]

No Title

I don't have a full length photo of the inside of the stern, here's a partial photo inside and a couple of the outside photos should give you an idea of how the boat is constructed. The photo labeled "outside motor mount area" I think shows that there's no distinct cap.

Yes, the transom wood is 100% shot which I pretty sure led to flexing.

Sounds like the consensus is, trailer the boat to a radiator shop & have it welded after I dig out the old wood.

Thanks all!

 

[Scott Danforth]

Yes, the transom wood is 100% shot which I pretty sure led to flexing.

Sounds like the consensus is, trailer the boat to a radiator shop & have it welded after I dig out the old wood.

Thanks all!

after you dig out the old wood, replace with new wood, then beat the cap back into place.

you may have to cut a few of the welds at the gunwal corners

 

[GA_Boater]

Can you get a pic of the wood inside? The wood may be fed up and in under that cap. They didn't do any welding with wood under the cap. I hope not.

 

[fishrdan]

Yes, have the transom cap welded. The wood "looks" OK to me from what can be seen in the pics, but you won't know what hidden damage is under the cap and transom skin, until you pull the transom.

I blew up the knee brace pic and it looks like the knee braces are loose, which would allow the transom to flex, and crack the cap. Also looking at the pics, all knee brace bolts don't appear to go completely through the transom, so they can be tightened. Myself, when reinstalling the knee brace bolts, add a washer to the outside and slather the bolts/washers with 3M 5200, then clean up the excess 5200 with paint thinner.

Pull the plywood transom and post some pics of what the wood looks like.

Don't use ACQ treated plywood (green stuff from the big box stores) if rebuilding the transom, it will literally eat your boat.

 

[GlormRax]

The transom wood is rotted through. I can push a screwdriver almost all the way through with no effort. I took the knee brace bolts out already which is why they are loose.

In order to get the wood out, I'm going to have to either cut the knee braces or cut the corners off & bend the cap up. I haven't decided which method to use yet. I'm leaning towards cutting the knees and then "patching" them with aluminum pieces. There's a good description of that method on another forum.

 

[Scott Danforth]

the best route is often the one that appears to be the most difficult.

your having the cap welded anyway.... cut the corner welds and bend